Heretofore, various walls such as bridge sections have been formed by piecemeal construction. That is, once a concrete section had been formed, a flexible rubber liner was placed on the end thereof, and the process repeated until an entire structure had been formed. Another method of assembly was to form alternating concrete sections, place the rubber liner on the end of each section and then form the remaining sections. Such methods were time consuming and costly.
U.S. Pat. No. 1,037,907 to Heltzel relates to a division plate which is insertable between concrete sections which form various items such as a curb.
U.S. Pat. No. 1,644,584 to Heltzel relates to a division plate having overlapping sections which are connected together through a pivot pin. The division plates contain an opening or slot which resides upon a side rail. After the concrete is poured, the division plates can be removed.
U.S. Pat. No. 2,359,214 to George relates to a core member for a mold having at least two substantially identical sections, a member hingedly connecting the sections together at one end and a spring spaced from the hinge end of the sections and normally urging said sections apart.
U.S. Pat. No. 2,610,381 to Rosati, et al, relates to a reuseable, demountable form which is used to build an overflow opening and an adjacent curb section of a road bed.
U.S. Pat. No. 2,626,444 to Wolf, et al, relates to a flexible form for integral concrete curbs and gutters.
U.S. Pat. No. 3,069,138 to Darby relates to a tied arch jacking frame for simultaneous pretensioning longitudinal and tranverse reinforcing rods used in making reinforced, prestressed concrete slabs.
U.S. Pat. No. 4,533,111 to Cousin relates to a system for constructing concrete barriers on a roadway with adequate spacing between sections of the barrier for proper drainage and expansion of the concrete where a temporary, removable core is located in the space between preparation of the concrete barriers and wherein said core contains an inner removable layer.